I went ahead and drilled 4 - 1/8" holes in the frame under the fore grip. Based on some discussions I've had and a lot of reading I figured out some thought it helped and some didn't. I can say that I think it helped some. I think that it will really help though later one when I go to a longer barrel or different caliber. I also added a o ring behind the top hat to help control the air flow some. Between the two changes it has helped a good bit. The one thing I can say is that if I was to buy another one I would get a .22 caliber instead of a .25. The talon ss is putting out just slightly more fpe than my p-rod. There very close, I think the prod is around 20 fpe and the talon is around 24 fpe. From what I'm reading a longer barrel will bring that up some more though. My wife is going to kill me when I tell her that I need another $100. I can hear her now, but you just spent how much on the one you just bought and now your wanting how much more?
If you put the longer barrel in you will not be able to use the sound loc kit and would have to add an ldc if you needed it to be back yard friendly. I used a high flow tank on my talon ss just to see how much fps i would gain. It was a .22 and i was able to push the 21 gr. pellets to 820 - 850 fps using the 12" barrel. The problem was the noise. You are pushing so much more air to get that velocity so the sound loc baffles cannot stop enough to keep it quiet. I would opt for a longer barrel and just add a shroud extension instead of getting the high flow tank for a 12" barrel.